Copper Alloy C17500
UNS C17500 · ASTM B441 · EN CuCo2Be, CW104C
C17500 (CuCo2Be, CW104C, ASTM B441) is a high-conductivity beryllium copper that uses cobalt rather than nickel to control grain growth during age hardening.
Reference datasheet — C17500 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the TF00 condition
C17500 tempers and conditions
C17500 is supplied in 6 conditions, soft to hard. TF00 is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution heat treated | Softest, most formable condition — pick for deep drawing, bending or machining before age hardening. | 190 | 310 | 30 | 85 HB | 22 % IACS |
Solution heat treated and cold worked, half hard | Intermediate strip/wire condition when some cold formability must be retained before aging. | 415 | 480 | 12 | 145 HB | 22 % IACS |
Solution heat treated and cold worked, full hard | Mill-hard strip/rod supplied for parts that will be stamped and then age hardened, or where only moderate strength is needed. | 500 | 550 | 8 | 160 HB | 23 % IACS |
TF00Default Solution heat treated and precipitation hardened | Standard stocked bar/plate condition for RWMA Class 3 welding electrodes, mold inserts and high-current contacts. | 620 | 760 | 15 | 23 HRC | 52 % IACS |
TD02 and precipitation hardened | Mill-hardened strip balance of strength and residual formability for stamped spring contacts. | 690 | 790 | 8 | 24 HRC | 52 % IACS |
TD04 and precipitation hardened | Highest-strength C17500 condition — for heavily loaded electrodes, springs and wear parts where conductivity must stay ≈45% IACS. | 760 | 830 | 7 | 27 HRC | 50 % IACS |
What is C17500?
C17500 (CuCo2Be, CW104C, ASTM B441) is a high-conductivity beryllium copper that uses cobalt rather than nickel to control grain growth during age hardening. Available as bar, plate and rod in TB00, TD02, TD04, TF00, TH02 and TH04, it is the standard choice for resistance welding electrodes and for springs and bushings needing strength with conductivity: 620 MPa yield, 760 MPa tensile, 15% elongation, 220 HB / 23 HRC / 96 HRB, 52% IACS, 215 W/m·K and service to 350 °C. Machinability is 40 and formability 35, and beryllium dust controls are mandatory; C17200 is the alternative where strength outweighs conductivity. C17500 has a density of 8.75 g/cm³ (0.316 lb/in³), lighter than 51% of copper alloy grades. It melts at 1,030°C (1,886 °F). C17500 has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 95% of copper alloy grades. Elongation at break is 15% and the elastic modulus is 138 GPa (20 Msi).
What is C17500 used for?
- Resistance welding electrodes
- Bushings/bearings
- High-conductivity springs
- Molds for glass/rubber
Advantages
- High strength — 620 MPa (89.9 ksi), better than 95% of copper alloy grades
- Stiff — 138 GPa (20 Msi), better than 95% of copper alloy grades
- High service temperature — 350°C (662 °F), better than 95% of copper alloy grades
- Conducts heat well — 215 W/m·K (124.2 BTU/hr·ft·°F), better than 80% of copper alloy grades
- High electrical conductivity — 52 % IACS, better than 80% of copper alloy grades
Limitations
- High embodied carbon — 6.5 kg CO₂/kg, worse than 94% of copper alloy grades
C17500 properties
Typical room-temperature values for C17500-TF00; bars are the position among copper alloy grades.
Physical3
C17500 has a density of 8.75 g/cm³ (0.316 lb/in³), lighter than 51% of copper alloy grades. It melts at 1,030°C (1,886 °F).
Mechanical14
C17500 has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 95% of copper alloy grades. Elongation at break is 15% and the elastic modulus is 138 GPa (20 Msi).
Thermal6
C17500 is rated for continuous service to 350°C (662 °F). It conducts heat at 215 W/m·K (124.2 BTU/hr·ft·°F), better than 80% of copper alloy grades. Thermal expansion is 17.6 µm/m·K (9.78 µin/in·°F).
Electrical3
C17500 conducts electricity at 52 % IACS, better than 80% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 58% of copper alloy grades.
Sustainability4
Producing a kilogram of C17500 takes about 95 MJ of energy and emits 6.5 kg of CO₂ — more than 95% of copper alloy grades. Typical recycled content is 30%.
Manufacturability7
C17500's machinability is fair (40/100, better than 57% of copper alloy grades); weldability good (60/100); formability fair (35/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the copper alloy family
Yield strength against density for every copper alloy grade FabDigit runs. C17500 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C17500
Is C17500 easy to machine?
Machines like a tough copper alloy at ~20–30% of AISI 1212; use sharp carbide, positive rake, flood coolant and local exhaust/wet methods to control beryllium-bearing dust.
Can C17500 be welded?
Resistance, GTAW and EB welding are practical with matching or Si-bronze filler; avoid oxy-fuel, and re-age after welding since the HAZ over-ages and softens.
Can C17500 be formed, bent or molded?
Form, bend or draw in TB00/TD02 then age at ~455–480 °C for 2–3 h; aged TH04 stock has little remaining ductility and cracks on tight bends.
C17500 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Be | 0.4 – 0.7 | 0.55 |
| CoNi may substitute for part of Co in some specs | 2.4 – 2.7 | 2.55 |
| Nicounted with Co in some registrations | ≤ 0.2 | |
| Fe | ≤ 0.1 | |
| Si | ≤ 0.2 | |
| Al | ≤ 0.2 | |
| CuCu + named elements ≥ 99.5 % | balance |
What surface finishes work on C17500?
Takes a high polish for mold inserts; readily nickel-, silver- or gold-plated after oxide removal — no anodizing (copper alloy).
Surface treatments FabDigit runs on copper alloy parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Equivalent designations
Standards and trade names that resolve to Copper Alloy C17500 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- B441
- EN / DIN / Werkstoff-Nr.
- CuCo2BeCW104C
How much does C17500 cost?
C17500 is a high-cost copper alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
C17500 — frequently asked
What is C17500 used for?
C17500 is typically used for resistance welding electrodes, bushings/bearings, high-conductivity springs and molds for glass/rubber. In short: cobalt-beryllium electrode copper; high conductivity plus strength; beryllium dust controls required.
What is the yield strength of C17500?
C17500 has a typical yield strength of 620 MPa (89.9 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 95% of copper alloy grades. Strength varies by condition: see the 6 listed tempers.
Is C17500 easy to machine?
Not especially — machinability is rated fair (40/100, better than 57% of copper alloy grades). Machines like a tough copper alloy at ~20–30% of AISI 1212; use sharp carbide, positive rake, flood coolant and local exhaust/wet methods to control beryllium-bearing dust.
Can C17500 be welded?
Yes — weldability is rated good (60/100). Resistance, GTAW and EB welding are practical with matching or Si-bronze filler; avoid oxy-fuel, and re-age after welding since the HAZ over-ages and softens.
What surface finishes work on C17500?
Takes a high polish for mold inserts; readily nickel-, silver- or gold-plated after oxide removal — no anodizing (copper alloy).
Can C17500 be formed, bent or molded?
Form, bend or draw in TB00/TD02 then age at ~455–480 °C for 2–3 h; aged TH04 stock has little remaining ductility and cracks on tight bends.
What is the maximum service temperature of C17500?
C17500 is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between C17500-TF00 and C17500-TB00?
TF00 is the default condition — standard stocked bar/plate condition for RWMA Class 3 welding electrodes, mold inserts and high-current contacts. TB00: softest, most formable condition — pick for deep drawing, bending or machining before age hardening. Yield strength is 620 MPa in TF00 versus 190 MPa in TB00.
How much does C17500 cost?
C17500 is a high-cost copper alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM B441 — Copper-Cobalt-Beryllium and Copper-Nickel-Beryllium Rod and Bar — ASTM (2019)
- Materion Alloy 3 (C17500) Technical Data — Materion Brush Performance Alloys (2021)
- CDA Alloy C17500 Properties — Copper Development Association (2023)
- ASM Handbook Vol.2 — Properties of Copper and Copper Alloys — ASM International (1990)
- EN CW104C (CuCo2Be) — Copper and copper alloys, wrought products — CEN (2016)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.